Roof construction



Feb. 24, 1948. .1. F. BLASKI ROQF CONSTRUCTION Filed July 11, 1945 2 Sheets-Sheet 2 I 17200745 07. I Q6/ 172, z

flu ywyh Patented Feb. 24,;1948 r U ITED? STATES?- PATEN: FICE.

ROOF CONSTRUCTION" John Blaski, Chicago, Ill.

Application July 11, 1945, Serial No. "$05,421:

6 Claims.

This invention relates to a construction for a roof or the like, and more particularlyto a panel or section from which such constructionmay befabricated.

In the building of a trussless roof for example,

namely,- that type characterized by an absenceof trusses andsupports distributed over the building area, and in whichthe roof is so contoured as-to enable it to be supported directly on the foundation, itis-highly-importantthat great rigidity be inherent therein, The absence or trusses, cross-braces and columns gives rise to problems-which mustbe solved-in the design of the panels or sections comprising-the roof, and embracing the factors of lateral and longitudinal thrust and direct loading.

While roofs of this general type have been heretofore known, many of them suffer from the shortcoming that insufficient' attention has been devoted to increasesin strength made possible by appropriate construction of the panels proper as contrasted with their mode of assembly, Thus, roof panel'sections have been proposed wherein the major or fiat extent of the panel has been corrugated in conventional manner and the panels are provided with simple flanges whereby adjoining sections maybe mutually secured. However, the corrugations do not continue intothe flanges to impart additional strength thereto, and the full benefit of proper flange construction 'hasnot been availed'of, IMoreover, panels for trussless roofs have been proposed in which no attempt has been made to conform the sections to the transverse curvature of the roof, for example, semi-elliptical, thus failing to utilize the greater load bearing ability of such curved sections.

My invention has for'its principal object the provision of a metallic roof orceiling panel preferably longer than-it is wide and having a transverse cross section which is substantially troughshaped, longitudinal marginalportions of the blank having been upturned to form thesides of thetrough, and the free edges-of the-sides being so formed as to be engageable with interlocking portions of adjac'entpanels for 'rapid;

assembly and disassembly;

A further object is to provide a panel as justdescribed in which one upturned side of the panel is bent outwardly upon itself to form an open fold or hem and the other or opposite upturned side is left unfolded. Thus adjacentsections may be overlappingly engaged by-means of the two different edge=formations aforesaidto' effect ar jointimpervious tothe entry of wind, moisture,

dust and other undesirable foreign elements. Moreover, it is a further aim-to provide the interengaging edges as aforesaid with registering apertures through which bolts, rivets or like 5.. means may be passed for-rapid erection or disassembly.

Anadditional objectcomprehends' the provision of; a panel as aforesa-idin which the upturnedsides-are of substantial depth in comlowparisonto the width of a section.

A further object resides-in the provision of trough-shaped panels as aforesaid=in which the bottom as Well asa-maior-portion ofthe sides are corrugated transversely in a novel manner,

the transverse cross; section of the corrugations consisting- 0in sine-curve and-the amplitude of the curvebeing a; maximum: at the center of the panel and 'gradually decreasing to-zero where the" corrugations are terminatedjust below the gq'einterengagingjoints -aforesaidf Anotherobject is to providein panels as aforesaidapertures-through-the bottom thereof at the two ends and adapted to" register with similar apertures inoverlappedadjacent sections and zs'means, for example,- rivetsor-bolts adapted to pass through said'apertures to maintain the sections in overlapped relation.

Still another object istoform' a panel constructed-- asaforesaid-with an areuate contour in a direction corresponding to 'the curvature of the roof at-a-= zone-- whereat the panel is to be installed: w

Incarryingoutthe-invention in one form I provide panels substantially longer than they are wide and having a--troughshaped-transverse cross section. Thepanels; are preferably preliminarily curved'by corrugating in the manner hereinafter described to correspond with the contour of a roof to be fabricatedtherefrom, for

40' example,- an arc of an ellipse; One upstanding side of the panel is'forrned initially slightly higher thanthe other-and-reversely' foldedto the exteriorto form a--narrow U-shapedflange or hem defining a channel just-sufficient in width to receive therein theadjacent; unfolded flange of an adjacent-panel, Each-of the {panels 5 is provided with apertures in; it s-twoupstanding sides, those apertures at the hem passingthrough both sides of the hem and-"wherebyitheinterengaged panels may be joined-instaggered-relationby means of bolts orrivets. At each end the panel is provided witha-pluralitypffapertures in order that endwiseadjacent panels, when assembled, may beoverlapped at their ends;-and---bolts or rivetspassed-through said apertures-iorfastening the same. For imparting additional rigidity to a panel and effecting the proper curvature thereof, it is corrugated in a novel manner, the major axis of each corrugation being disposed transversely of the panel and the corrugations jointly forming a sine curve in planes longitudinally of the section and normal to the surface thereof. The corrugations are characterized by being of maximum amplitude in the plane passing through the medial axis of the panel, and the amplitude of the curve beinggradually decreased until there is reached a line just below the interengaging edges of adjacent sections.

In the drawings, which show a preferred form of the invention and certain alternative embodiments thereof:

Fig. 1 is a somewhat schematic cross section taken transversely of a roof fabricated from the panels of my invention; 7

Fig. 2 is a plan view of a portion of the roof of Fig. 1, also somewhat schematic;

Fig. 3 is a detailed plan view of a panel;

Fig. 4 is a detailed side elevational view of the panel of Fig. 3; V v

Fig. 5 is a cross sectional view taken on the line 55 of Fig. 2;

Fig. 6 is a partial detailed plan view of a portion of the roof of Fig. 2 and on larger scale;

Fig. 7 is a cross sectional view taken on the line '|1 of Fig. 5; 7

Fig. 8 is a cross sectional view taken on the line 8-8 of Fig. 5;

Fig. 9 is a cross sectional view taken on the line 9-9 of Fig. 5;

Fig. 10 is a chart to indicate the form of the corrugations in their relation to the panel;

Fig. 11 is a cross sectional view, similar to Fig. 5, of an alternative form of panel; and

Fig. 12 is a cross sectional view, similar to Fig. 5, of another alternative form of panel.

Directing attention now to Figs. 1 and 2, I have shown a trussless roof ill comprising the panels of my invention, the contour of the roof being indicated as semi-elliptical and supported on foundations ll. As clearly seen in Fig. 2, the panels l2 are preferably arranged in rows transversely of the roof and with the panels of a row staggered. with respectto those in adjacent rows. A suflicient number ofsuchrows is employed to comprise a complete roof.

In Figs. 3 and 4 there is shown a, single panel l2 comprising a single thin sheet of metal, e. g.. galvanized steel formed in a punch press or otherwise into a trough-shaped transverse cross section (Fig. 5), the bottom H! of the panel being preferably flat and the sides Hi and I5 joining the bottom in segments of a substantially cylindrical surface of substantial radius. The side M is initially lower than the side I5 and, the latter is then reversely folded in the press the exterior of the 4 within the scope of the invention to preform the end zones of the hem to receive such overlapped panels.

Adjacent the upper edge of the sides l4 and i5 the panel is provided with a plurality of equally spaced apertures 2| (Figs. 4 and 5), the apertures being so situated with respect to each other and the ends of the panel as to permit endwise overlapped panels in any selected row to be readily fastened to similarly overlapped panels in adjacent rows. Bolts 22 or rivets may be passed through the apertures 2| for maintaining the assembled panels in predetermined position and in rigid relationship. It will be understood that the panel to yield a narrow downwardly-disposed U- shaped flanged edge or open hem Hi. The interior of the hem I6 is made of sufficient width to receive snugly therein the unfolded edge M of the adjacent panel or panels. 7

It will be understood that the thickness of the metal used for a panel will depend upon the strength desired to be imparted thereto. In general, this thickness will be such that the hem l6 may, at the time of erection, be opened wider with a screw driver or similar tool in order that two endwise overlapped panels may be received within the hem as will be pointed out hereinafter. If the thickness of a panel will not permit ready deformation of the fold 15 inthe field it is panels may, if desired, be fabricated without the apertures 2| and that the same may be punched in the field before or after assembly by means of a suitable punch and die. Alternatively the joined sections may be welded.

From Fig. 4 it will be noted that each panel is preferably preformed into arcuate contour along its longer axis, the curve imparted to a panel corresponding to the curvature of that portion of the roof the panel is intended to occupy. Due to the rigid nature of a panel it is not ordinarily a simple matter to curve the same during erection although it is possible, by reason of the corrugations to be described, to curve a panel, to lit the contour of the roof without the specific initial forming aforesaid. That is to say, the forming of a roof panel having a generally U-shaped or trough-like transverse cross section to provide a particular arcuate contour along the longitudinal axis, as clearly indicated in Fig. 4, would, in the :absence of the corrugations, result in an indiscriminate buckling of the sheet. The upstanding sides not only would tend to resist bending thereof in an edgewise direction, but to resist the arcuate forming of the substantially horizontal bot- ;tom portion. In a roof section of relatively heavy termination in the sides of the trough, the material of theblank is shortened by a maximum amount along its central longitudinal axis and by a gradually lesser amount along the two sides, thereby imparting the arcuate contour to the panel as seen in Fig. 4. By regulating the amplitude of the corrugations and the rate of diminution of the amplitude as aforesaid, any desired contour, within reasonable limits, may be provided. Otherwise stated, by changing the amplitude, any desired crimping of the metal may be achieved over specific longitudinal segments of the panel, while the resulting corrugations serve to stifien the sheet.

At each of its ends the panel I2 is provided with a series of spaced-apart apertures 24 whereby, upon endwise overlapping of the panels in a row, bolts or rivets may be passed therethrough to fasten the panels together.

In Fig. 6 a portion of an assembled roof comprising panels llla, [0b, I00 and 10d is shown. The preferred method of erection would consist in first assembling the endmost row of panels including Illa, beginning at ground level, then engaging panels such as lllb, lllc, etc., for the adjacent row, the panels being overlapped in the acac a-43:

downercof: .direction-ibotnway from the ridge or. center: line 10f; .thecroofg: the; hem. l6 Y of the row- Lab, lllc; etc; being engaged. over-the unhemmed' side llttojrtherowe Illa; etc; Eon greater. rigidity.-

its ,endwise joints staggered 'with respect to thosein the a preceding.- row.- It is .toJce notedthat the hem;,l.6 of; an up-roofi'panel" overlies the hem l6 or'the: lowerxdown-roof panel.- r Thu shedding of" rain is ..1: r.operly-- GfiECtCd iHOtL only: as to. these longitudinal joints-but as to the transverse joints 28. It will be understood that alternate rows will include panels of half lengthwhere necessary to enable erection in staggered relation as. described.

A primary feature of the invention resides in the novel manner of corrugating the panels. The corrugations 25.; (Figs. 3, 4 and 5) arecontinuous over the bottom I3 and the. major portion of the sides ld andJS (Fig. 5) and are disposed transversely. ofathe longer axis of: a. panel. The corrugations follow one another. and are not distributed inspaced apart relation, any plane passing througha longitudinal elementof the panel andperpendicular to the surface ofthe panel intersecting; all said corrugations to-form a sine curve corresponding to the formula;

y 1* sinwhere y is the ordinate measured from the aXis of a: for

any point of the curve 1' is the amplitude and a: is the abscissa of the point.

At the longitudinal axis of the panel 1' is a maximum, and the corrugations terminate just below the zone of overlap of a hem IS with a side M, at which line the parameter r is zero.

In Figs. '7, 18 and 9 are shown three typical cross sections transversely of a group of corrugations 25, from which figures taken in conjunction with Fig. 5 it will be noted that over substantially the entire flat portion of the bottom l3 the corrugations are of maximum amplitude, and that the amplitude decreases as the line of termination of the corrugations is approached on either side. The chart of Fig. 10 illustrates this reduction of the amplitude from a maximum value of r(r=1) to zero.

The selection of a sine curve for the cross sectional contour of the corrugations allows the reduction of the depth thereof from maximum to zero with a linear decrease of stress absorption. That is to say, as the stresses on the panel decrease from the central axis to the sides the corrugations decrease in depth linearly proportionately, Thus no abrupt change from the deeper portions of a corrugation to the shallower portions thereof i encountered as would be the case using corrugations whose cross sectional contour consists of the conventional arcs of a circle joined end to end or of any curve other than the sine curve. Any such abrupt changes set up localized lines of weakness with consequent danger of rupture under stress. My invention eliminates this disadvantage by providing an uninterrupted transfer of stress from one longitudinal narrow zone of a panel to the next narrow zone and thus progressively from the center toward the sides where the verticall disposed portions of the panel offer a greateremom'entaofiinertiaato absorb bend:- i ing stressandthe-corrugationsineedinoti-be:of full: depth.- Moreover :rby terminating the cor-ruga tions below; the aoverla'ppingajointsof: adjacent. panels the hem 16 and its mating edgee-ld-ymaybe closely interlocked ito effectza tightgxweatherproof joint.

In Figs.- 1'1" andiil23are=shown cross: sectional views correspondingtodzhat of fig efii but of alter-. nate embodiments: of my invention: For certain.

types .ofs'roofsiit' maybe-foundiadvisable to modify the transverse general; cross. section of a panel my invention,' it;will be understood, of course, that.

I; :do not: wish to be limited thereto sincemany modifications may bemade; 'and Igzthe-refore; contemplate theappended claim'srto cover any such modifications as. fall within= the :true spirit andscope. oflmy invention;

Having thus desc'i'ibed my invention; what- I claim andidesire to 'secure by-Letters- Patent is:

1.' A structuralpanel adapted for--use-in multiple in=aroof or-th'elike -comprisinga relatively thinblankmarginally bent to fOI-Il'rfi; troughshaped member. having a substantially segmental: cylindricallongitudinal configuration, the bottomof the member and the major extent of the sides thereof being provided with a plurality of corrugations disposed transversely of the member, the depth of the corrugations being a maximum over substantially the entire width of said bottom and gradually decreasing on both sides toward zero at the free edges of said sides, whereby said graduated corrugations provide the said segmental cylindrical configuration without buckling of the member, one longitudinal edge of the panel being provided with an outwardly turned-over lip adapted to overlie the adjacent upturned lip of a neighboring panel.

2. A structural panel adapted for use in multiple in a roof or the like comprising a relatively thin blank bent to form a trough-shaped member, corrugations transversely of the axis of thememher, the amplitude of the corrugations being a maximum in a plane longitudinally centrally of the member and the amplitude decreasing gradually from both sides of said maximum toward the free edges of the sides of the member, the depth of the corrugations in the said plane reducing the length of the member to the greatest extent in said plane and to a gradually lesser extent towards the said free edges to provide a panel of predetermined substantially segmental cylindrical longitudinal configuration free from buckling, one longitudinal edge of the panel being provided with an outwardly turned-over lip adapted to overlie the adjacent unturned lip of a neighboring panel.

3. A structural panel adapted for use in 'multiple in a roof or the like comprising a relatively thin flat blank bent to form a trough-like member, corrugations transversely of the axis of the member, the amplitude of the corrugations being a maximum in a plane normal to and disposed centrally longitudinally of the member and the amplitude decreasing gradually on both side of said plane toward the free lateral edges of the member, whereby uniform curvature longitudinally of the member is-provlded without buck ling, one longitudinal edge oi the panel being provided with an outwardly turned-over lip adapted to overlie the adjacent unturned lip of a neighboring panel.

4. The method of forming a structural panel from a flat blank which method comprises bending two opposed marginal lateral portions of the blank to provide a trough-like member, and transversely eorrugating the member to impart an arcuate longitudinal configuration to the member, the corrugations being impressed to a maximum in a zone substantially centrally longitudinally of the member and shallower at the ends of the corrugations, the corrugations terminating in the sides of the members.

5. The method of forming a structural panel from a flat blank, which method comprises bending the blank to provide a trough-like member,,

and transversely corrugating the member to impart an arcuate longitudinal configuration to the member, the corrugations being impressed to a maximum in a plane normal to the member and passing through the longitudinal central axis thereof and shallower at the ends of the corruga- 25 corrugations disposed transversel of the longi:

tudinal axis of the member, the amplitude of the corrugations being maximum in a plane normal to and disposed centrally longitudinally of the member and the amplitude decreasing gradually on both sides of said plane toward the longitudinal edges of the upturned sides of the member, whereby the panel is provided with a curvature longitudinally of the member, one edge of the member having a plurality of apertures spaced apart along the length of the member, the opposite edge having a downturned lip adapted to engage the unturned lip of an adjacent panel and both the lip and side of the member adjacent thereto having a plurality of apertures therethrough and spaced along the extent thereof in register with the apertures of the unturned edge of the adjacent panel.

. JOHN F. BLASKI.

, REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 483,192 White Sept. 2'7, 1892 1,406,980 Crawford Feb. 21, 1922 1,617,069 McLaughlin Feb, 8, 1927 1,771,028 Bronson July 22, 1930 2,238,566 Perrine Apr. 15, 1941 2,271,451 Blaski Jan. 27, 1942 2,333,908 Wilkofi Nov, 9, 1943 2,355,707 DeBoer Aug. 15, 1944 2,365,934 Black Dec. 26, 1944 February 24, 1948. JOHN F. BLASKI appear in the printed specification of the above l mmbered patent reguiring correction as follows: Column 4, line 61, for the word I J 807:

read unturned; and that herein that the same 0rd of the case in the Patent Ofiice.

THOMAS F. MURPHY,

Assistant Oommz'ssz'oner of Patents. 

